The present invention relates to an electronic drum.
In a conventional electronic drum, a drum head or a pad is struck by a stick, and a vibration caused thereby is converted into an electrical signal. A musical tone (electronic tone) generating operation of an electronic tone source apparatus (such as a PCM tone source or an FM tone source) is controlled by waveform information of the electrical signal (striking position as a function of time, tone volume, and the like), thereby generating an electronic tone from a loudspeaker. In particular, the electronic drum must satisfy the following requirements: even if any portion of the drum head or pad is struck, the output (i.e., sensitivity) from a pickup device must be uniform; a change in signal in accordance with a change in striking force coincides with feeling of a performer; and a stick feeling must resemble that of an acoustic drum. Therefore, the material of the drum head and its mounting structure determine the performance of the electronic drum. Various drum heads have beer proposed, and for example, Japanese Utility Model Publication No. 59-39753, Japanese Utility Model Laid-Open Nos. 55-97792 and 58-113070 are known.
However, in an electronic percussion disclosed in Japanese Utility Model Publication No. 59-39753, outer peripheral portions of two vibration films are bonded to each other, and a cushion member and a pickup device are arranged between the vibration films to constitute a drum head. Therefore, a means for supporting and tensing the drum head is necessary as in an acoustic drum, resulting in a complicated structure and poor handling. In addition, sensitivity variation occurs depending on striking positions. In an electronic percussion disclosed in Japanese Utility Model Laid-Open No. 55-97792, a reception member is disposed in an opening of a cylindrical body, a cushion material is placed on the reception member, and the cushion material is covered with a striking film. However, with this electronic percussion, the striking film must be supported and tensed at a predetermined tensile force. Therefore, the structure is complicated, and sensitivity variation occurs as in the above mentioned electronic percussion.
In a snare drum trainer disclosed in Japanese Utility Model Laid-Open No. 58-113070, a foamed member is disposed on the surface of a base, and a dummy head is adhered thereon. With this structure, although good stick feeling can be obtained, it is nothing but a trainer, and cannot be satisfactorily used for performance.
As another conventional apparatus, the following electronic drum is known. More specifically, as shown in FIG. 4, a drum head 1 is tensed on a cylindrical body 2 by a known support/tension means 3, and a cushion member 5 is arranged between the drum head 1 and an intermediate plate 4. A dynamic loudspeaker 6 as a microphone is mounted on the lower surface of the intermediate plate 4. With this electronic drum, stick feeling can resemble that of the acoustic drum. However, since the electronic drum of this type has poor high-frequency characteristics, a delicate stick work cannot be easily detected. In addition, since the loudspeaker 6 has a large thickness, the thickness of the drum is inevitably increased. It is therefore difficult to realize a low-profile electronic drum.